On to engines. In the petrol range, the entry-level A 180 variant is likely to be popular, featuring a 1.4-litre 136hp unit available with either 6-speed manual or 7G-DCT dual-clutch auto transmission. This same engine's offered in the A 200 with 163hp, which manages rest to 62mph (in the manual model) in 8.2s. Next up is the A 250, which uses a 2.0-litre petrol powerplant in a 224hp state of tune, manages rest to 62mph in 6.2s and is only offered with a 7G-DCT auto 'box. Mercedes also offers an A 250e petrol plug-in hybrid variant, which uses a 1.33-litre petrol engine mated to a 75kW electric motor linked to a 15.6kWh battery and offers 44 miles of WLTP-rated electrified driving range.
There are three diesel alternatives, all offered only as automatics. The first is the A 180d, which puts out 116hp and uses the 7G-DCT auto gearbox. Next up is the A 200d which has a 2.0-litre 150hp engine. Beyond that lies the top A 220d, which tunes the same unit up to 190hp. The A 200d and A 220 use an 8G-DCT auto. At the top of the range are the two Mercedes-AMG 2.0-litre petrol turbo hot hatch variants. There's the A 35 4MATIC which offers a potent 306hp. And the A 45 S 4MATIC+, which has 421hp.
What else do you need to know? Well the suspension is the usual torsion beam rear set-up on most models, but if you go for a variant with 4MATIC AWD, you'll get a more sophisticated multi-link rear set-up. The 'DYNAMIC SELECT' driving modes system is standard, as usual enabling you to tweak steering feel and throttle response. At extra cost, adjustable damping can be added into it. Some of the autonomous driving capability from larger Mercedes models has been built into this one, meaning that, in certain situations, you're a-Class, if appropriately equipped, will effectively be able to drive itself on dual carriageways at cruising speeds.
There's a choice of five-door hatch or saloon body shapes. Either way, from the outside, this fourth generation A-Class delivers a more progressive design with a low bonnet and flat, more angular LED headlamps. The car is visually extended by its now longer wheelbase and a smart character line along the side. The bonnet slopes down more heavily than in the preceding model series, emphasising the more dynamic, upright front. Larger wheel arches housing bigger rims (ranging from 16 to 19 inches) help too, making this A-Class sit more squarely on the road. This MK4 design has a wider look at the rear end thanks to a more heavily waisted greenhouse and at the rear, there are slim, two-section tail lights.
It's the interior that sees the really big changes though. The usual instrument binnacle cowl has been completely dispensed with, so the wing-shaped main body of the dashboard can extend from one front door to the other with no visual discontinuity. A virtual instrument screen (of either 7-inches or 10.25-inches in size) replaces the usual dials and can be joined with a centre-dash infotainment display (again either 7-inches or 10.25-inches in size) to create one continuous monitor, much as you get in larger Mercedes models. That extra wheelbase means more interior space - and with the hatch, the 370-litre boot is 29-litres larger than before too.
Prices for mainstream models start at around £25,000, which gets you either the A180d diesel variant or the petrol A200. There are seven trim levels - 'SE', 'Sport', 'Sport Executive', 'AMG Line', 'AMG Line Executive', 'AMG Line Premium' and 'AMG Line Premium Plus'. There's a choice of five-door hatch or four-door saloon models. The saloon requires a premium of around £600 over the hatch and misses out on base 'SE' trim.
Every A-Class model comes well equipped. The entry-level 'SE' trim features twin seven-inch displays including a central touchscreen with MBUX multimedia system featuring 'Hey Mercedes' voice activation. Plus there's comfort suspension, 16-inch alloy wheels, a DAB radio, Artico man-made leather and Bertrix fabric upholstery, Active Lane Keeping Assist, Speed Limit Assist, a Keyless-Go starting function and air conditioning. The 'Sport' trim line adds LED high performance headlights, 17-inch alloy wheels, Artico and 'Fleron' fabric upholstery and automatic climate control. 'AMG Line' customers will benefit from 18-inch AMG alloy wheels, an AMG bodystyling kit, Artico and Dinamica microfibre upholstery and a three-spoke sports steering wheel.
This fourth generation A-Class is much better connected than before. Navigation functions, for example, can now be based on traffic feedback from so-called 'Car-to-X communication' where information gets fed in from other similarly-equipped road users. As usual, there's a dowloadable 'Mercedes Me' app that connects you into your car and can tell you things like local fuel prices or the availability of parking spaces at your destination.
Let's get to the WLTP figures. The economy champion of course, is the A 180d variant, which in base trim manual form exhales just 120g/km of CO2, while only drinking a gallon of fuel on the combined cycle every 61.4 miles. With respectable performance figures, it's a tempting package - albeit one that in its standard form, forgoes the big wheels and aggressive bodykits of more dynamic-looking versions. If you plan on adding the extra features, then economy will obviously take a hit. The A 200d manages up to 58.9mpg in manual form and 134g/km. And the A220d auto returns up to 57.7mpg and 129g/km.
As for the petrol engines, well the A 180 and A 200 in manual form both manage up to 47.9mpg on the combined cycle and 134g/km of CO2, figures that change to 47.1mpg and 135g/km if you go for auto transmission. The auto-only A 250 2.0-litre petrol variant manages 41.5mpg and 155g/km. The A 250e plug-in hybrid manages 256.8mpg and 25g/km of CO2.
The warranty may be an industry standard 3 years but is for unlimited miles, handy to know if you spend a lot of time on the road. Just remember that a mid-range diesel is the sensible option for high resale figures. With that in mind, something like a mid-spec A180d model might well represent the sweet spot of the range. On the other hand, an 4MATIC petrol variant with every option thrown at it will lose a lot more of its value over the years.
Mercedes turned things around with its third generation A-Class, recreating it into the kind of car a younger, sportier buyer could consider. This sleeker, more sophisticated, bigger and better connected fourth generation model version continues that theme and lays down quite a challenge to its Audi A3 and BMW 1 Series rivals.
And in summary? Well those who can afford the asking prices and like the driving experience will find this contender sporty, self-assured and possessed of a feel-good factor that really does make you feel special if you've specced your chosen variant correctly. Which is exactly what owning a car of this kind should be all about.